The present invention relates to methods to make basic aluminum halides, such as basic aluminum chlorides. The present invention further relates to basic aluminum halides, such as basic aluminum chlorides made by the one or more processes of the present invention.
Basic aluminum chlorides are useful in the manufacture of active ingredients for antiperspirants, as coagulants in water treatment, and in the manufacture of alumina catalysts and supports, as well as other uses. Basic aluminum chloride is known by other names, such as aluminum chloride hydroxide, aluminum hydroxychloride, aluminum chlorhydroxide, polyaluminum chloride, aluminum oxychloride, aluminum chlorohydrate, and aluminum chlorhydrate. The exact nomenclature varies with the industries using the products. For example, the antiperspirant industry tends to call these materials basic aluminum chlorides or aluminum chlorohydrates, whereas the water treatment industry typically refers to them as polyaluminum chlorides, and the catalyst industry typically refers to them as aluminum chlorohydrates or aluminum sols. In U.S. Pat. No. 3,476,509, incorporated in its entirety by reference herein, a process is described to make water-soluble basic aluminum halide compounds, which includes the use of a water-soluble thallium compound for catalytic purposes. However, the use of a thallium salt is just not a viable approach today due to the fact that thallium salts are on the List of Extremely Hazardous Substances mandated by §302 of the Emergency Planning and Community Right-to-Know Act of 1986 (SARA Title III EPCRA Extremely Hazardous Substances).
Accordingly, it would be useful to find alternative mechanisms to make basic aluminum halide compounds, especially basic aluminum chlorides, which have the advantages achieved with a thallium catalyst, but without the use of an extremely hazardous substance.